As it is generally known, high levels of data traffic traversing a networking device in a communication network may result in congestion. In existing systems, when congestion occurs, networking devices typically treat all voice and/or multi-media application communication sessions alike, because of they lack the ability to differentiate between individual sessions. This lack of session and/or call information at traffic aggregation points in a network may result in perceivable decreases in performance for voice and/or multi-media applications in the face of network congestion. Using current networking protocols and techniques, when sufficient data traffic aggregation occurs at one or more networking devices, packets will be dropped without regard to the specific sessions they belong to. As a result, reduced Quality of Service (QoS) caused by congestion conditions effects sessions of converged applications, such as voice and multi-media applications. Additionally, lack of knowledge of session information at networking devices at the edge of the communication network (“edge devices”) may result in lack of security, due to vulnerability to certain types of attacks.
One potential solution to these problems is establishing guaranteed bandwidth tunnels between gateway networking devices. For example, using protocols such as RSVP-TE (ReSerVation Protocol with Traffic Engineering), and tunneling mechanisms such as MPLS (MultiProtocol Label Switching), IP GRE (Internet Protocol Generic Routing Encapsulation), VPN (Virtual Private Network), etc., guaranteed bandwidth tunnels can be created. However, this approach has significant drawbacks, including the following:
i) Available bandwidth in networking devices of the converged network cannot effectively be shared, since a full mesh topology is created between the gateway devices.
ii) Scaling and provisioning may be difficult when the number of gateways and session end points is large, because of the resulting full mesh topology. Adding or removing a gateway device may result in a need to re-provision all gateway devices in the network.
iii) Most enterprise networking devices cannot support complex end-to-end tunneling mechanisms.
iv) Soft clients, such as SIP (Session Initiation Protocol) phones on a personal computer, can't participate in tunnels.
These problems militate away from a solution based on guaranteed bandwidth tunnels. Similarly, if managing guaranteed bandwidth tunnels is an overly complex approach, managing session based tunnels would also be even more difficult, since sessions are between two or more application end points, possibly on different trusted or un-trusted software and hardware platforms, and may be dynamic, as when a voice call is established when needed, and torn down after use. Moreover, converged application components have no knowledge of the operational details of the network cloud that connects them.
Accordingly, for the above reasons and others, it would be desirable to provide granular network service at the session level, within networking devices of a converged data network. It would further be desirable to provide session specific information for use in edge networking devices, so that they can mitigate security problems by treating traffic not belonging to an established session using best effort techniques.